Dialkoxyphosphonomethyl derivatives of hydantoins

ABSTRACT

Dialkoxyphosphonomethyl-hydantoin derivates, which can be used for rendering plastics and fibres noninflammable, are described along with their methods of preparation and use.

United States Patent [191 Porret et al.

[ Dec. 9, 1975 [54] DIALKOXYPHOSPHONOMETHYL DERIVATIVES OF HYDANTOINS [75] Inventors: Daniel Porret, Fresens, NE; Jiirgen Habermeier, Pfeffingen, both of Switzerland [73] Assignee: Ciba-Geigy Corporation, Ardsley,

[22] Filed: Feb. 7, 1975 [21] Appl. No: 548,050

Related US. Application Data [63] Continuation-impart of Ser. No. 347,527, April 3,

1973, abandoned.

[30] Foreign Application Priority Data Apr. 4, 1972 Switzerland 4893/72 [52] US. Cl. 260/309.5; 260/30.6 R; 260/45.7 P;

260/45.8 N [51] Int. Cl. C07D 233/72 [58] Field of Search 260/309.5

[56] References Cited UNITED STATES PATENTS 2,928,841 3/1960 McConnell et al. 260/309.5

Primary ExaminerNatalie Trousof Attorney, Agent, or Firm-Luther A. R. Hall [57] 0 ABSTRACT 7 Claims, No Drawings 3,925,406 1; 2 i v R and R preferably each denote an alkyl or alkenyl DIALKOXYPI-IOSPHONOMETHYL DERIVATIVES j group with l to 4 carbon atoms, especially the methyl OF HYDANTOINS or ethyl group, but also the propyl, butyl, allyl, butenyl This application is a continuation-in-part of copendor monochloroethyl group. I ing application, Ser. No. 347,527, filed Apr. 3, 1973, 5 Ypreferably represents an alkylene group, such as now abandoned. The invention relates to dialkoXyphosthe methylene, ethylene, butylene, hexylene or dodecyphonomethyl-hydantoins and dialkoxyphoslene group, or an alkylene group interrupted by heterophonomethyl-dihydrouracils, processes their manuatoms, such as 3-oxapentamethylene. facture and their use for rendering plastics and fibres A prime objectiveof this invention relates to the non-inflammable. H I i y I T preparation of dialkoxyphosphonomethyl derivatives Flameproofing agents containing phosphorus are alof hydantoin from the corresponding 1N- ready known. In order to achieve a favourable effect, halogeno methyl derivatives of hydantoin as useful considerable amounts of these agents, in most cases flame retardants for a variety of polymeric systems. mor than 10%, must be added to the plastics to be pro- The N-halog enomethyl derivatives are directly contected, but this. frequently has unfavourable effects on verted to the corresponding phosphonate esters using the plastics to be protected in other, respects, for examphosphite esters, such as triethyl phosphite, in the wellple mechanical respects. It has now been found that the known Arbuzov reaction. I phosphorus-containing compounds according to the The phosphonate esters attached to hydantoin moiinvention render plastics non-inflammable if they are eties are particularly useful asflame retardants possessadded in such amounts that the phosphorus content is ing as they do both nitrogen and phosphorus. The parat least 0.8 4%. ticularly efficacious activity as flame retardants of cer The compounds according to invention corretain moleculescontaining both nitrogen and phosphospond to the formula I or I I i rus is well-known as described by J. W. Lyons, The

l? Z c o, /OR, HN NCH2P (l) c oR,

mo z -c=o O=C--Z OR,

i CH N N Y N N CH i 1') fi/ fi 0 0 in which 2 denotes a nitrogen-free divalent radical Chemistry and Uses of Fire Retardants, Wiley-Interwhich is necessary to complete a five-membered or sixscience, New York, 1970, pp. 20-21 189, 354-357. membered ring and denotes ,a divalent aliphatic, cy- 4 Phosphonates are widely useful as flame retardants in cloaliphatic or araliphatic radical andR as well as R many polymeric systems including cellulosics ibid, pp. each represent an alkyl oralkenyl group which can be 184-189, polyurethanes, pp. 354-357, and polyesters, substituted, for example by halogen, .or together reprepp. 373-3 74, 398-401. In the latter case the phosphosent an alkylene group with 2 to 5 carbon atoms. nates are often incorporated into polyester melts where Z preferably represents a methylene group which can they self-polymerize and tranesterify with the polyester be substituted by alkyl groups R and R with 1 to 6 carinvolved. The phosphonate ester derivatives of bisbon atoms or a cycloalkylidene group. Z can be-espehydantoinsof this invention are useful as flame retarcially the isopropylidene group, also the nor isodants in a variety of polymeric systems. propylmethylene group, the cyclohexylidene group or The compounds according to theinvention are mancyclopentylidene group or an ethylenefgroup which is ufactured by reacting the compounds of the formula II optionally substituted by alkyl groups with 1 to 4 caror II bon atoms, such as the ethylene, the 1,2-dimethylethyl I lene, the 2,2-dimethylethylcne or the l-methyl-2-isoin which X denotes chlorine or bromine, with a trialkylpropylethylcne group. phosphiteof the formula III l wherein R denotes an optionally substituted alkyl or alkenyl group.

For the reaction, which corresponds to a Michaelis- Arbusov reaction, the mixture is usually warmed for several hours to above 100C, preferably l20-l60C, whereupon R X distills off. R X is, for example, ethyl chloride, ethyl chloride, butyl chloride .or 1,2- dichloroethane.

The starting substances of the formula II or ll for the manufacture of the compounds according to the invention are obtained by reaction of the corresponding hydroxymethyl compounds with compounds which introduce chlorine or bromine, for example with acid halides, such as SOCL SOBr oxalyl chloride, PCl PCl PBr POCl or hydrogen chloride or hydrogen bromide.

The compounds according to the invention, of the suspension with the powdered polymer and removing compounds of the formula IC or IV the solvent or suspending atent. The effective amount of the substance according to the invention depends on the material to be protected and on the structure of the phosphorus-containing compound. The minimum active amount is however surprisingly low: in general, a phosphorus content of 2 to 4% in the material already suffices in order to render this material non-inflammable.

EXAMPLE 1 3Dimethoxy-phosphonomethyl-5,S-dimethylhydantoin I A mixture of 529 g of 3-chloromethyl-5,S-dimethyl- I hydantoin (3,0 mols) and 447 g of trimethylphosphite (3,6 mols) is warmed to 150C internal temperature (bath temperature l20l60C) over the course of 70 minutes, during which strong refluxing occurs. The methyl chloride produced in the reaction is condensed ina cold trap at 80C in order to control the course of l H i (V) R preferably represents hydrogen, or the methyl,

ethyl, hydroxyethyl, ethoxyethyl or phenyl group.

The reaction is appropriately carried out at elevated temperature, for example from 40 to 100C, optionally with the addition of an acid or basic catalyst, such as hydrogen chloride or triethylamine, and in the presence of solvents or diluents, such as alcohols or dioxane.

The products according to the invention are liquid to crystalline substances which are colourless in the pure state. They can be purified by recrystallisation or vacuum distillation.

On incorporation into polymers or their starting substances, thex impart non-inflammability thereto. Where they still contain an active hydrogen atom (compounds of the formula I) they are capable of glycidylation, ethylolation and other reactions, for example the formation of adducts with epoxide resins.

For example, they can be added to epoxide resin-curing agent mixtures before the curing reaction is carried out. They can also be incorporated into the polymeric material by kneading, for example by dissolving or susthe reaction. After a period of a further 2 hours the elimination of methyl chloride is complete and l50 g of methyl chloride (99,7% of theory) are obtained. The reaction product is freed of readily volatile constituents, such as. excess trimethylphosphite, at C in a water pump vacuum and is subsequently dried to con stant weight at 0.1 mm Hg and 90C.

780 g of a yellowish, crystalline crude product are obtained and purified by recrystallisation from 500 ml of methyl ethyl ketone. 543.2 g of 3-(methaneposphonic acid dimethyl ester)-5,S-dimethylhydantoin 5 ,5-dimethylhydantoinyl-3 )-methanephosphonic acid dimethyl ester or 3- (dimetho xyphosphonomethyl )-5 ,S-dimethylhydantoin] (72% of theory) of melting point ll2l l3.2 C are obtained.

Elementary analysis: found: calculated:

38.4 7: C 38.41% C 6.2 7: H 6.04 '7: H 11.3 7: N 11.2 2' N 12.771P 12.38%?

The HNMR spectrum is reconcilable with the fol- CH P (OCH EXAMPLE 2 3-Diethoxyphosphonomethyl-S ,S-dimethylhydantoin Elementary analysis: found. calculated:

10.06 '70 N 10.07 K- N The H-NMR spectrum is reconsilable with the following structure:

EXAMPLE 3 3-Diethoxyphosphonomethyl-5 ,5-pentamethylenehydatoin Analogously to Example 1, 216 g of 3-chloromethyll,3-diazaspiro-[4,51-decane-2,4-dione 1.0 mol) and 199.5 g of triethylphosphite (1.2 mols) are treated for 3 hours 40 minutes at 120 to 146C internal temperature. Thereafter, 16.6 g of triethylphosphite (0.1 mol) are added and the mixture is left to react for a further 3 hours 20 minutes. After working up analogously to Example l, 299 g of a brown, highly viscous crude product (93.9% of theory) are obtained. Crystallisation from toluene: cyclohexane, 1:5, and subsequent distillation of the crystals in a bulb tube at 152-154C/0.05 mm Hg yields B-(methanephosphonic acid diethyl ester 1 ,3-diazo-spirol 4.5 ]-decane-2,4-dione thoxy-phosp honomethyl-S ,ipentamethylene-hydantoin) of melting point 102-104C.

The HNMR spectrum agrees with the following structure:

0 0 t g Hll\ /N-CH (OCH CH EXAMPLE 4 3-Di-n-butoxy-phosphonomethyl-5,S'dimethyIhydan- I toin 68.6 g of 3-chloromethyl-5,S-dimethylhydantoin (0.388 mol) and 90.5 g of tri-n-butylphosphite (0.466

mol) are warmed to C internal temperature and thereafter the heating is removed since an exothermic reaction takes place. The internal temperature rises.

over the course of 4 minutes to 144C, whilst the butyl chloride eliminated is distilled off. Thereafter the mix ture is kept at 144-152C internal temperature for a further 3 hours 50 minutes to complete the elimination of butyl chloride. [Butyl chloride eliminated 339g (89.2% of theory)|. The working up takes place analogously to Example 1, and 1 17.9 g of a clear, yellow, vis-, cous crude product (90.8% of theory) are obtained.

A crude product distilled in a bulb tube at C/O.4 mm Hg gave a colourless, viscous distillate having the following analytical data:

Elementary analysis found: calculated:

49.77 K 50.29 7! C 11.02 71 H 8.14 H 14.73 '71- N 8.38 71 N 9.00 74 P 9.26 71 P The HNMR spectrum is essentially reconcilable with the following structure:

EXAMPLE 5 3 ,3 '-Methylene bis( l-diethoxyphosphonomethyl-5,S-dimethylhydantoin) Analogously to Example 1, 18.26 g of bis-( 1- chloromethyl-S ,5-dimethylhydantoinyl-3 )-methane (0.05 mol) and 19.9 g of triethylphosphite (0.12 mol) are reacted for 4 hours and 30 minutes at an internal temperature of l 10-142C. After working up according to Example 1, 28.1 g of a brownish, clear, highly viscous product (99,0% of theory) having the following analytical data are obtained:

The analysis agrees with the following structure: clamped Dln Sta d bar (120X15Xl0 of the O CH CH n c-ca -o t N/ Cfi/O-C H -CH P-CH -N N-CH N-CH P B Z' o-cn -CH 1 I 1 0 EXAMPLE 6 plastic to be tested is vexposed for 1 minute to the flame th 1 of a bunsen burner fed with town gas and inclined at ijs gz gggf 15 45 (burner orifice: 9 mm, flame height with burner 4 standing vertica11y: cm), so that the 15 mm wide sur- 5,5 dimethylhydantom) I I face of the test specimen is 3 cm above the upper edge 0f -Chl0F0methyl'5 ,5 F y of the burner and the end face isat a horizontal dishydantolrlyla mol) and g of meth' tance of 1 cm from the bottom edge of the burner. y p p H101) are react ed, analog u y Level 1 denotes that after removing the flame the bar Example for 6 hours at 105 The'workmg p does not continue to burn for more than 15 seconds. It

takes place analogously to Example 1 and 38.0 g of a is com arabl withc t 2 5 R 1 210 b yellow, highly viscous crude product (99.3% of theory) time 8 seionds) egory o l i ummg containing 9.5% of phosphorus are obtained.

A crude product distilled in a bulb tube at 220C/0.3 mm Hg gave a yellowish highly viscous distillate with the following elementary analysis:

EXAMPLE 11 A mixture of 100 parts of the phosphonate manufactured according to Example 2, 180 partsof tris-epoxide fundi required from 1,3-bis-(5,5-dimethylhydantoinyl-3)-propan-2- 48.3 7. c 48.9 %c 30 01, containing 6.1 epoxide equivalents per kg, 131.8 Z 3 Z: gig parts of methylnadic anhydride and 2 parts of tetra- 9.5 7. P 9.70 P methylammonium chloride strength in methanol) is processed according to Example 1 and cured in 2 hours at 120C and 20 hours-at 150C. The analysis agrees with the following structure: 35 The cured moulding has the following properties CH CH 11 C 3 o 3 H C 0 0- c c- 3 o 0-C H P-CH N N- [CH 1 N N-CH P 2 2 5 2* if i H Examples Of applications Phosphorus content 2.74%

lnflammability (CTM 20) level 1/8" EXAMPLE I Heat distortion point according to Martens I (DIN) 89C V A mixture of 100 parts of the phosphonate manufac- Flexural strength (VSM 77,103) 4.7-8.2 kp/mm Deflection (VSM 77,103) 1 3.4-7.9 mm

tured according to Example 2, 180 parts of a triglycidyl compound from 1 ,3-bis-(5 ,5 -dimethy1hydantoiny1- 3')-propan-2-o1, containing 6.1 epoxide equivalents/kg, 1 14 parts of hexahydrophthalic anhydride and What is claimed is:

2 Parts of tetl'amethylmnmonium Chloride 1. A dialkoxyphosphonomethylderivative of hydanstrength in methanol) is worked into a homogeneous m f the f l mass at C and subsequently poured into aluminium moulds prewarmed to C. Curing takes place in 2 fi hours at 120C and 20 hours at C. 7 P cH., N N Y Mouldings having the following properties are ob- 60 R Impact strength (VSM 77,105) 6.0-8.0 cmkg/cm tained: I

Phosphrus content 0 2.8% P

lnflammability (CTM 20*) 1 level III" V O=CZ O OR Heat distortion point according to Martens 82C 5 N/ \N CH u/ (DlN) Flexural strength (VSM 77,103) 8.0-11.0 kp/rnm' Deflection (VSM 77,103) 3.9-5.0 mm 0R2 lmpact strength (VSM 77,105) 8.S-11.0 cmkg/cm" *CTM 20: Description of the test A horizontally O wherein 4. A compound according to claim 1 wherein Y denotes alkylene of 1 to 6 carbon atoms or 3-oxapentamethylene.

5. A compound according to claim 1 wherein R and R are methyl or ethyl.

6. A compound according to claim 4 which is 3,3- methylenebis-( 1-diethoxyphosphonomethyl-5 ,5 -dimethylhydantoin).

7. A compound according to claim 4 which is 3,3- hexamethylenebis-( l-diethoxyphosphonomethyl-5 ,5

dimethylhydantoin). 

1. A DIALKOXYPHOSPHONOMETHYL DERIVATE OF HYDANTOIN OF THE FORMULA
 2. A compound according to claim 1 wherein Z denotes isopropylidene.
 3. A compound according to claim 1 wherein Z denotes cyclohexylidene.
 4. A compound according to claim 1 wherein Y denotes alkylene of 1 to 6 carbon atoms or 3-oxapentamethylene.
 5. A compound according to claim 1 wherein R1 and R2 are methyl or ethyl.
 6. A compound according to claim 4 which is 3,3''-methylenebis-(1-diethoxyphosphonomethyl-5,5-dimethylhydantoin).
 7. A compound according to claim 4 which is 3,3''-hexamethylenebis-(1-diethoxyphosphonomethyl-5,5-dimethylhydantoin). 